NEW Computer client prompted to reboot after software update deployment

[Michael Ballack]

This is using MS SCCM 2012 r2 with sp1 Server. This is a single SCCM server with all the roles, to support up to 200 client computers. We are using this SCCM for software updates deployment for win 7, win8, w2k8 r2, and w2k12 r2 desktop/laptops and servers. We were scheduled to have the patches deployment every 2 months. We did all these update packaging and deployment manually without using ADR (automatic deployment rule). However, users always feedback that they saw their computer notification to require to reboot once in a while in a month's time. We also conducted a further checking on update group's settings to ensure that server/workstation won't reboot after the deployment. But, still the reboot notification popping up. We are quite sure windows updates is disabled in these workstations. What else should we do to stop this mystery?

Thanks in advance.